Flong for stereomolds.



UNITED STATES PATENT OFFICE.

THOMAS JAMES CLARKE DREWETT, OF LONDON, ENGLAND.

FLONG FOR STEREOMOLDSi $PECIFIOATION forming part of Letters Patent No. 678,381, dated July 16, 190;.

Application filed March 13, 1901.

To all whom it may concern:

Be it known that I, THOMAS JAMES CLARKE DREWETT, a subject of the King of Great Britain and Ireland, and a resident of London, England, have invented a certain new and useful Improved Flong for Stereomolds, (for which I have filed an application for British patent, No. 2,895, dated February 11, 1901;) and I do hereby declare the following to be a full, clear, and exact description of the same.

This invention relates to the manufacture of flong for use in obtaining stereomolds, its objects being to avoid the disadvantages incidental to fiong as ordinarily made by the users thereof from day to day in quantities sufficient for immediate needs of a plurality of sheets of blotting and tissue papers pasted together and kept moist by Wet blankets until required for usenamely, the constant repetition of the preparation of the fiong, which is irksome to and needs special attention by and wastes the time of the stereotyper; the necessity of keeping the flong moist to prevent it from drying and hardening, which renders it liable to go bad and to be unevenly and unduly wetted; the beating of the fiong into the form and the consequent liability of injuring the face of the type and necessitating frequent renewal thereof; the liability of obtaining an irregularly-beaten or thick-andthin stereomold and consequent inability of removing the latter from the form, especially when the fiong is unduly wet, without liability of injuring it, and the consequent necessity of drying the mold on the form, which provents the obtainment of stereomolds of wood blocks and the like in association with typematter on account of the liability of the high temperature required to dry the mold to injure the blocks, and the liability of the mold to undue shrinkage-and to produce improved fiong which can be made in large quantities on an industrial scaleas a new article of manufacture and stocked as a marketable commodity in a dry condition and which will keep for a considerable time unafiected in its re quired qualities by atmospheric influences and available and suitable for instant use upon being merely sufficiently damped, as well for taking stereomolds of wood or process-blocks, engraved plates, and the'like,

Serial No. 51,021. (No model.)

whether alone or associated with type-matter,

as for taking stereomolds of type-matter alone,

ing, and to be expeditiously dried without any or with but little shrinkage.

To this end the invention is characterized by the manufacture of fiong in single-sheet form by subjecting sheets of bibulous unsized or blotting paper of suitable thickness to the consecutive treatments hereinafter described, which confer upon the sheet the qualities of enabling it to receive when very moderately damped and under a very moderate pressure a perfect impression from type, wood, or processblocks, engraved plates, and the like; a homogeneity of substance and density, which enable the mold to be removed from the form withoutliability of injury for drying; quickness of drying with moderate heat and with little, if any, shrinkage; considerable power of heat resistance, which enables the mold to be repeatedly used for the production of stereoplates, and a good face, forming the desiderata of a perfect fiong, while also attaining the aforesaid advantages of enabling the fiong to be made as a marketable commodity and stored in a dry condition for a considerable time unafieoted in its required qualities by ordinary atmospheric influences and in a condition available for immediate use upon being merely sufficiently damped.

In carrying out the invention the paper sheet is first impregnated and coated on each sidewith a sem'iliquidmixture of dextrine or gum-arabic and alum by brushing or otherwise applying such mixture thereon or thereto, and the coated paper is then dried or allowed to dry. Each side of the paper is then further coated or treated with a pastelike preparation of' the following ingredientsnamely, rye-flour, Russian glue, gilders whiting, borax, starch, and black or Scotch treacle-and the so-treated paper is then dried or allowed to dry, when it results in the improved fiong.

The first treatment mixture may consist of about eight parts of dextrine or gum-arabic and about three parts of alum dissolved in forty parts of water, and the second treatment mixture may be compounded by mixing about sixty-four parts of rye-flour in one hundred and sixty parts of water and boiling the same to a paste-like consistency, soaking and dissolving about sixteen parts of Russian glue in twenty parts of water and mixing the same with the warm rye paste, letting the rye-glue mixture stand until it ferments, mixing about one hundred and twenty-eight parts of gilders whiting in one hundred and twenty parts of water to a paste-like consistency and mixing the same with the fermented rye -glue mixture, mixing together about four parts each of starch, borax, and black treacle and mixing the same with the rye-glue-whiting mixture, and letting the whole stand for sufficiently long to deposit any sediment; but such exact proportions are not arbitrary.

As the improved flong only requires to be very moderately damped (which may be done bya roller-pad or by any other suitable means) to sufficiently soften it to enable it to immediately receive a perfect impression under a very moderate pressure, it can be pressed into the form bya press orby any suitable means of evenly applying such a pressure and when so pressed immediately yields a sharp and perfect stereomold in a sufficiently dry and homogeneous condition to enable it to be removed from the form without liability of injury and separately dried, and it can be so expeditiously treated that with its use a stereoplate can be obtained in much less time from the form being ready for making the matrix than when using ordinary flong.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. The manufacture of flong for stereomolds in single-sheet form by coating sheets of bibulous unsized or blotting paper on each side with a semiliquid mixture of dextrine or gum-arabic and alum, drying the same, further treating or coating the same on each side with a paste-like preparation of rye-flour Russian glue gilders whiting borax starch and black treacle, and drying the same, as set forth.

2. Flong for stereomolds made in singlesheet form of bibulous unsized or blotting paper coated on each side firstly with a semiliquid mixture of dextrine or gum-arabic and alum and secondly with a paste-like preparation of rye-flour Russian glue gilders whiting borax starch and black 'treacle, as set forth.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

v THOMAS JAMES CLARKE DREVETTA \Vitnesses:

CHARLES AUBREY DAY, ALFRED CHARLES DAY. 

